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Synchrounous motor is three phase motor,but its not self
starting .why?
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Answer Posted / leo thomas
Since the rotor is supplied from a DC source the rotor have
a permanent polarity . But applying 3 phase supply to
stator, a 3 phase magnetic field is produced , but polarity
changing according to the supply frequency . Actually at
some regular time intrvals the stator poles and rotor poles
comes into exat 120 degree phase shift (this will exist
only for some micro seconds)the motor try to rotate a
clockwise direction . Another time intervels motor getting
torque to counter clockwise direction .
Thus the rotor poles oscillating to clockwise and
anticlockwise direction, due to the inertia of the moving
system it cannot move into any direction
| Is This Answer Correct ? | 2 Yes | 3 No |
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